Fired by Gucci America Inc., a former network employee allegedly retaliated by using his knowledge of the luxury retailer’s computer system to wreak havoc.

Sam Chihlung Yin, 34, is now being prosecuted by the Manhattan District Attorney’s office, accused of creating a virtual private network token in a fictitious employee’s name while he still worked at Gucci and then using it to trick the information technology department into giving him access to the network after he left, according to the Jersey Journal and Techworld.

He allegedly deleted corporate email boxes, destroyed some files and shut down servers for 24 hours at one point, costing the company some $200,000 in lost sales and restoration expenses.

“Computer hacking is not a game. It is a serious threat to corporate security that can have a devastating effect on personal privacy, jobs, and the ability of a business to function at all,” says New York District Attorney Cyrus R. Vance Jr. in a press release.

Yin is charged in a 50-count indictment with computer tampering, computer trespass, falsifying business records, identity theft and other crimes. If convicted, he could be sentenced to as much as 15 years in prison.